Projector and control method therefor

ABSTRACT

A projector can be easily attached by mounting a connecting unit to a socket for illumination in an ordinary home. Since the projector includes a communication unit configured to receive an electronic mail, the projector updates an image signal and adjusts a diffusion degree of modulated light by a light-diffusion adjusting unit on the basis of contents of the mail received by the communication unit. Therefore, when a user desires to inform family members who will return home that the user suddenly has to go out, if the user transmits in advance, to the projector, a mail including a message for a family member who returns home, the family member who returns home turns on an illumination switch at the entrance, whereby the projector can start up, perform an illuminating function, and clearly project and display the message.

The entire disclosure of Japanese Patent Application No. 2012-162387,filed Jul. 23, 2012 is expressly incorporated by reference herein.

BACKGROUND

1. Technical Field

The present invention relates to a projector that can function aslighting equipment and a control method for the projector.

2. Related Art

In a company, a public office, or the like, staff members often hold ameeting for a large number of people while projecting materials on awall surface or the like of a meeting room using a projector. In such ameeting, for example, when data of a prepared material is wrong, thestaff members sometimes desire to replace the material in a hurry. Forexample, JP-A-2009-3356 (Patent Literature 1) discloses a techniquesuitable for such a situation. Specifically, a receiving function or thelike is added to the projector, whereby, when an emergent electronicmail is received, a material attached to the electronic mail isprojected instead of a projected material.

JP-A-2005-99588 (FIG. 6) (Patent Literature 2) and JP-A-2006-227143(Patent Literature 3) propose a projector including a component (a plug)for mounting (fixing) the projector to a socket for lighting equipmentand capable of switching an illuminating function and a video projectingfunction using electric power received from the socket.

However, the technique disclosed in Patent Literature 1 is based on thepremise that the projector is used in the meeting room of the companywhere the projector is set. Therefore, a scene of usage is limited. Inparticular, in ordinary homes, many families do not own the projectoritself and do not have an opportunity for using the technique.Therefore, versatility of the technique is poor.

On the other hand, with the technique proposed by Patent Literatures 2and 3, by mounting the projector to the socket for lighting equipment,the illuminating function and the projecting function can be switched.However, there is no description concerning a specific method, forexample, in what kinds of situations the two functions are switched(properly used). Therefore, it is difficult to effectively utilize thetwo functions.

SUMMARY

An advantage of some aspects of the invention is to solve at least theproblems described above, and the invention can be implemented as thefollowing application examples or forms.

APPLICATION EXAMPLE 1

This application example is directed to a projector including: aconnecting unit for mounting the projector to a socket for lightingequipment; a light source configured to emit light with electric powersupplied to the connecting unit; a light modulating unit configured toconvert the light emitted by the light source into modulated lightspecified by an image signal; a diffusion adjusting unit configured toadjust a diffusion degree of the light made incident on the lightmodulating unit or the light emitted from the light modulating unit; acommunication unit configured to receive predetermined information via acommunication network; and a control unit configured to update the imagesignal and control the adjustment of the diffusion degree by thediffusion adjusting unit on the basis of contents of the predeterminedinformation received by the communication unit.

With this configuration, for example, by mounting the connecting unit toa socket for lighting equipment set in an entrance hall of an ordinaryhome, the projector that can also function as lighting equipment can beeasily attached. The projector includes a communication unit configuredto receive predetermined information such as an electronic mail. Theprojector can update the image signal and adjust the diffusion degreeusing the diffusion adjusting unit on the basis of contents of thepredetermined information received by the communication unit.

Therefore, for example, when a user desires to inform family members whowill return home that the user suddenly has to go out, if the usertransmits in advance, to the projector, an electronic mail including amessage for a family member who returns home, the family member whoreturns home turns on an illumination switch at the entrance, wherebythe projector can start up, perform the illuminating function, andclearly project and display the message. Therefore, it is possible toeffectively utilize the illuminating function for illuminating theentrance hall and the projecting function for displaying the message. Inother words, it is possible to provide the projector that caneffectively utilize the illuminating function and the projectingfunction and has high versatility.

In the projector of the application example, it is preferable that thecontrol unit switches, on the basis of the contents of the predeterminedinformation, an illumination mode for causing the diffusion adjustingunit to diffuse the light and a projection mode in which the diffusiondegree is lower than the diffusion degree in the illumination mode.

In the projector of the application example, it is preferable that, whencontent for display is included in the received predeterminedinformation, the control unit superimposes the content on the imagesignal and sets the diffusion degree to the projection mode.

In the projector of the application example, it is preferable that, whencontent is included in the received predetermined information, thecontrol unit superimposes, on the image signal, an image indicating thatthe content is being read before performing superimposition of thecontent.

In the projector of the application example, it is preferable that, whena link to content is included in the predetermined information, thecontent is read from the link destination via the communication network.

In the projector of the application example, it is preferable that theprojector further includes a storing unit configured to store settingdata including an image signal used in the illumination mode, and, whenelectric power is supplied to the connecting unit, the control unitcauses, on the basis of the setting data, the light modulating unit tomodulate the light emitted by the light source.

In the projector of the application example, it is preferable that thesetting data includes the image signal including an image having agradation of tones.

In the projector of the application example, it is preferable that thesetting data includes, in addition to the image signal, at least one ofdiffusion degree data representing the diffusion degree of the diffusionadjusting unit, an identifier for designating the illumination mode orthe projection mode, illumination color data designating an illuminationcolor in the illumination mode, and time data designating duration ofthe illumination mode or the projection mode.

In the projector of the application example, it is preferable that thediffusion adjusting unit includes a PDLC device or a reverse mode PDLCdevice.

In the projector of the application example, it is preferable that thediffusion adjusting unit includes a focus adjusting lens or a diffuserconfigured to transmit and diffuse the light.

APPLICATION EXAMPLE 2

This application example is directed to a control method for a projectorincluding: a connecting unit for mounting the projector to a socket forlighting equipment; a light source configured to emit light withelectric power supplied to the connecting unit; a light modulating unitconfigured to convert the light emitted by the light source intomodulated light specified by an image signal; a diffusion adjusting unitconfigured to adjust a diffusion degree of the light made incident onthe light modulating unit or the light emitted from the light modulatingunit; and a communication unit configured to receive predeterminedinformation via a communication network, the control method including:allowing the communication unit to receive the predeterminedinformation; and updating the image signal and controlling theadjustment of the diffusion degree by the diffusion adjusting unit onthe basis of contents of the predetermined information received by thecommunication unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a diagram of a form of a usage scene of a projector accordingto a first embodiment.

FIG. 2 is a schematic configuration diagram of the projector mainlyincluding an optical system.

FIG. 3 is a schematic configuration block diagram of the projector.

FIG. 4 is a flowchart for explaining a flow of a control method for theprojector.

FIGS. 5A and 5B are diagrams showing examples of a mail for operationinstruction for the projector.

FIG. 6A is a driving timing chart in a normal mode.

FIG. 6B is a driving timing chart in a high-speed mode.

FIG. 7 is a block diagram showing a form of a specific hardwareconfiguration.

FIG. 8 is a flowchart for explaining a flow of a control methodaccording to a second embodiment.

FIG. 9 is a diagram showing an example of a mail for operationinstruction.

FIGS. 10A and 10B are diagrams showing forms of images in anillumination mode.

FIGS. 11A and 11B are diagrams showing different forms of a lightdiffusing device.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Embodiments of the invention are explained below with reference to thedrawings. In the drawings referred to below, scales of layers andregions are set different from actual scales in order to show the layersand the regions in sizes recognizable on the drawings.

First Embodiment Overview of a Projector Usage Scene

FIG. 1 is a diagram of a form of a usage scene of a projector accordingto a first embodiment. First, an example of a usage scene of a projector100 according to this embodiment is explained.

The projector 100 is a projector that can be attached to a socket forillumination set in an ordinal home. In the example shown in FIG. 1, aconnecting unit (a plug) of the projector 100 is fixed to a socket 34for lighting equipment (a lighting fixture) set on a ceiling 33 of anentrance hall 30. The projector 100 can switch an illumination mode inwhich the projector 100 functions as the lighting equipment (thelighting fixture) and a projection mode in which the projector 100functions as a projector. A specific configuration, a switching methodfor the two modes, and the like are explained below.

FIG. 1 shows a situation in which, when a family member returns to thehouse where the family is out at night, the family member turns on anillumination switch 32 for an entrance hall, whereby a message left byanother family member is projected on a floor 35 of the entrance hall 30by the projector 100. On a projection screen (a floor surface), “Welcomehome. I'm out on urgent business and will be back around 20:00.” This isbecause the family member (e.g., a wife), who had to suddenly go out,transmitted a message for the family member (e.g., a husband), whoreturned home at night, to the projector 100 by electronic mail(hereinafter referred to as “mail”).

Initial setting for the projector 100 is the illumination mode. When theillumination switch 32 is turned on, illumination is started. At thispoint, if content included in a received mail (predeterminedinformation) is a message mainly including a text, the illumination modeis switched to message display in about a few seconds. Therefore, it ispossible to transmit a message while the family member locks a door 31or takes off shoes. In particular, when the illumination mode isswitched to the projection mode, since the brightness and the color toneof illumination change, it is possible to cause the family member tophysically (visually) recognize the presence of the message. In theprojection mode, as in the illumination mode, illuminance sufficient forthe family member to recognize an object around the family member atnight is secured.

Configuration of the Projector

FIG. 2 is a schematic configuration diagram of the projector mainlyincluding an optical system. FIG. 3 is a schematic configuration blockdiagram of the projector. The configuration of the projector 100 forrealizing the functions explained above is explained.

As shown in FIG. 2, the projector 100 assumes a configuration in which aconnecting unit 9 functioning as a plug (a cap) is attached to one end(surface) of a substantially cylindrical case 40. In other words, theprojector 100 is formed in an external appearance of a rather long(elongated) electric bulb. The projector 100 is not limited to thisshape. The projector 100 may be formed in any shape as long as the case40 and the connecting unit 9 are integrally formed. For example, theprojector 100 may be a spherical body, may be a polygonal body, or maybe a solid body obtained by combining the spherical body and thepolygonal body.

The connecting unit 9 is a power receiving terminal (a plug) screwedinto and fixed to a cap socket, which is an example of a power supplyterminal for lighting equipment, and configured to receive the supply ofelectric power from the cap socket. The electric power supplied to theconnecting unit 9 may be either an alternating current or a directcurrent. The connecting unit 9 may be a plug connected to a receptaclefunctioning as a power supply terminal.

The projector 100 includes a light source 1, a light source controller 2configured to drive the light source 1, a spatial-light modulatingdevice 3 configured to modulate light emitted from the light source 1, adisplay controller 4 configured to write an image in the spatial-lightmodulating device 3, an irradiation optical system 5 provided toirradiate the light from the light source 1 on the spatial-lightmodulating device 3, a projection optical system 6 configured to projectthe light modulated by the spatial-light modulating device 3, a lightdiffusing device 7 configured to adjust a diffusion degree of the lightprojected by the projection optical system 6, and a light diffusioncontroller 8 configured to control the light diffusing device 7 and thelike. The light source unit is configured by the light source 1 and thelight source controller 2. A light modulating unit is configured by thespatial-light modulating device 3 and the display controller 4. Adiffusion adjusting unit is configured by the light diffusing device 7and the light diffusion controller 8.

As shown in FIG. 3, the projector 100 further includes a control unit10, a power supply circuit 17, an IR receiving unit 11, and an interfaceunit 18 and the like.

The control unit 10 is an MCU (Micro Controller Unit). The control unit10 controls the units such as the light source controller 2, the displaycontroller 4, the light diffusion controller 8, the IR receiving unit11, and the interface unit 18. A storing unit 19 is attached to thecontrol unit 10. The storing unit 19 includes a nonvolatile memoryincluding a flash memory, a ROM, and a RAM. The nonvolatile memory hasstored therein various programs for controlling the operation of theprojector 100 including a program specifying order and contents forperforming the illumination mode and the projection mode and dataaccompanying the programs. The programs also include a driving programfor switching the illumination mode and the projection mode according topresence or absence of reception of predetermined information (a mail,etc.) and contents of setting data included in the predeterminedinformation. The accompanying data includes setting data for initialillumination including an image signal in an initial illumination mode,diffusion degree data, and driving mode data specifying a drivingfrequency in sequential driving of a light source and a plurality ofsetting data set for each of usage scenes such as setting data for aparty and setting data for relaxation. The ROM has stored therein aBIOS.

The power supply circuit 17 is an AC conversion circuit configured toconvert alternating-current power supplied to the connecting unit 9 intodirect-current power. The power supply circuit 17 includes atransforming circuit, a rectifying circuit and a stabilizing powersupply circuit such as a switching regulator. When electric powersupplied to the connecting unit 9 is a direct current, the transformingcircuit and the rectifying circuit are unnecessary. The power supplycircuit 17 also functions as a detecting unit configured to detect thatelectric power is supplied to the connecting unit 9.

The IR receiving unit 11 is a light receiving unit configured to receivean operation signal by an infrared ray received from a remote controller(not shown in the figure) for remotely controlling the projector 100.The interface unit 18 is configured by a communication unit 12, an SSD13, a memory card unit 14, and the like.

The communication unit 12 is a wireless LAN adapter. The communicationunit 12 can receive predetermined information such as a mail transmittedfrom an external network (not shown in the figure) to the projector 100.The communication unit 12 realizes a function of an actual communicationunit by forming a pair with the control unit 10 that assumes a functionfor identifying and analyzing predetermined information out ofcommunication data received by the communication unit 12. With such acommunication unit (the pair of the control unit 10 and thecommunication unit 12), it is also possible to access a server computer,a personal computer, a smart phone, or a tablet computer on the outside(all of which are not shown in the figure) via an external network andread out image data, moving image data, and the like.

The SSD 13 is a flash memory drive device. The memory card unit 14includes a card slot for a memory card and an I/O (Input/Output)circuit. An image to be projected by the projector 100 is stored in amemory card (not shown in the figure) inserted into the card slot. Thestored image can be rewritten through the external network by thefunction of the communication unit 12.

In this specification, “image” is defined as a term including a stillimage and a moving image. The still image includes a still image thatchanges with time such as a slide show and may involve sound. “Image”sometimes means a displayed or projected still image or moving imageitself or sometimes means data (including streaming data) for displayingor projecting the still image or the moving image.

Referring back to FIG. 2, the light source 1 includes an LEDcorresponding to R (red light), an LED corresponding to G (green light),and an LED corresponding to B (blue light). In the followingexplanation, the light source 1 is represented as RGB light sources 1R,1G, and 1B as well. R, G, and B are an example of a combination oftypical element colors for displaying a full color. Therefore, the lightsource 1 in this embodiment includes three LEDs corresponding to threedifferent element colors. However, in other embodiments, the lightsource 1 may include LEDs corresponding to four or more differentelement colors or may include LEDs corresponding to two differentelement colors. The light source 1 may include, instead of the LEDs,organic or inorganic semiconductor lasers or organic EL(electroluminescent) elements or may include phosphors, excitation lightsources of which are LEDs or lasers. In the following explanation, lightsynthesized by the light sources 1R, 1G, and 1B is referred to as“illumination light”. A color tone of the illumination light is referredto as “illumination color”. The illumination color is specified byillumination color data of setting data.

The irradiation optical system 5 includes a dichroic prism configured tocombine optical paths of color lights from the respective RGB lightsources 1R, 1G, and 1B, an integrator including a fly-eye lens, and apolarization conversion element configured to align polarized lights oflights from the integrator into one light.

The spatial-light modulating device 3 in this embodiment is asingle-panel transmissive liquid crystal light valve. A liquid crystallight valve in this context includes a pair of sheet polarizers and aliquid crystal panel located between the pair of sheet polarizers. As apreferred example, the RGB light sources 1R, 1G, and 1B and thespatial-light modulating device 3 are driven by an RGB sequentialsystem, i.e., a color sequential system. Consequently, the projector 100can project full-color illumination or image.

The light diffusing device 7 is located on an optical path of lightprojected by the projection optical system 6. The light diffusing device7 includes a transmissive reverse mode PDLC device. PDLC refers topolymer-dispersed liquid crystal. Although not shown in the figure, thereverse mode PDLC device includes a pair of electrodes having opticaltransparency and a reverse mode PDLC layer located between the pair ofelectrodes. When there is no potential difference between the pair ofelectrodes, the reverse mode PDLC layer assumes optical transparency. Asa result, light is transmitted through the light diffusing device 7without being substantially diffused. The light diffusing device 7 atthis point is expressed as being in a non-diffusing state. On the otherhand, when a predetermined potential difference is given between thepair of electrodes, the reverse mode PDLC layer assumes opticaldiffusibility. As a result, the light is diffused and transmittedthrough the light diffusing device 7. The light diffusing device 7 atthis point is expressed as being in a diffusing state. Further, when thepotential difference given between the pair of electrodes is anintermediate potential difference between 0 and a predeterminedpotential difference, the reverse mode PDLC layer assumes intermediateoptical diffusibility corresponding to the potential of the reverse modePDLC layer. As a result, the light is moderately diffused andtransmitted through the light diffusing device 7. The light diffusingdevice 7 at this point is expressed as being in an intermediatediffusing state. In this way, the light diffusing device 7 can adjust adiffusion degree of an image or illumination projected by the projector100.

Transparency obtained when the reverse mode PDLC layer assumes theoptical transparency is higher than transparency obtained when a normalPDLC layer assumes the optical transparency. This is one of advantagesrealized when the light diffusing device 7 includes the reverse modePDLC layer (or the reverse mode PDLC device). The term “PDLC” is definedto include both “reverse mode PDLC” and normal “PDLC”.

Operation of the Projector

FIG. 4 is a flowchart for explaining a flow of a control method for theprojector. A flow of a driving method including the switching of the“illumination mode” and the “projection mode” described above isexplained mainly with reference to FIG. 4 and with reference to FIGS. 1and 3 as well. The flow is executed by the control unit 10 controllingthe units including the communication unit 12 on the basis of thedriving program stored in the storing unit 19.

First, the illumination switch 32 is pushed to be turned on and electricpower is supplied to the connecting unit 9.

In step S1, initialization of the units is performed. Specifically,electric power is supplied from the power supply circuit 17 to the unitsincluding the control unit 10 and the communication unit 12 to start upthe units. Subsequently, the control unit 10 reads out the setting datafor initial illumination from the storing unit 19, sets initial drivingmode data for a light source in the light source controller 2, and setsinitial image signal data in the display controller 4. Further, thecontrol unit 10 sets initial diffusion degree data in the lightdiffusion controller 8. In this embodiment, the initial setting data isset in the illumination mode.

In step S2, the control unit 10 executes lighting in the illuminationmode specified by the setting data for initial illumination.Specifically, the control unit 10 drives to light the RGB light sources1R, 1G, and 1B to synthesize white light at a driving frequency of a“high-speed mode” explained later and displays a solid image on thespatial-light modulating device 3. A color of illumination is notlimited to white and may be other colors (e.g., orange).

In step S3, the control unit 10 adjusts a light diffusion degree of thelight diffusing device 7 to the illumination mode. Specifically, thecontrol unit 10 adjusts the light diffusion degree to a diffusion degreeat which the outer edge of projected light is blurred. To facilitateunderstanding of the explanation, the two steps S2 and S3 are dividedlyexplained. However, actually, the two steps are substantiallysimultaneously performed as a pair.

In step S4, the control unit 10 determines whether a mail (predeterminedinformation) is received. Specifically, the control unit 10 checkswhether a mail is included in communication data received through thecommunication unit 12. When a mail is included in the communication data(Yes in S4), the control unit 10 proceeds to step S5. When a mail is notincluded in the communication data (No in S4), the control unit 10returns to step S2 and continues the lighting in the illumination modeof the initial setting. In this embodiment, a mail is used as an exampleof the predetermined information. However, other communication data suchas a control command or packet data including an identifier may be used.

In step S5, the control unit 10 checks and analyzes contents of thereceived mail. Specifically, the control unit 10 reads setting data outof the contents of the mail. The setting data includes an identifier foridentifying the illumination mode or the projection mode, driving modedata, image signal data, and a message and the like.

In step S6, the control unit 10 determines whether the received mailinstructs the illumination mode. Specifically, the control unit 10checks whether the identifier for selecting the illumination mode or theprojection mode is 0 or 1. When the received mail instructs theillumination mode (Yes in S6), the control unit 10 proceeds to step S7.When the received mail does not instruct the illumination mode (No inS6), the control unit 10 proceeds to step S8.

In step S7, the control unit 10 sets the setting data designated by thereceived mail in the units. Specifically, the control unit 10 sets thedriving mode data in the light source controller 2 and sets the imagesignal data in the display controller 4. The control unit 10 sets thediffusion degree data in the light diffusion controller 8. When thesetting of the setting data designated by the received mail ends, thecontrol unit 10 proceeds to step S2 and executes lighting in theillumination mode according to the setting data.

In step S8, the control unit 10 stores the setting data in theillumination mode being executed. This is for the purpose of storing,before switching the illumination mode to the projection mode, thesetting data being executed. In this step, since lighting is sometimesperformed according to setting data different from the setting data forinitial illumination, it is possible to reuse the setting data byleaving the setting data in the storing unit 19.

In step S9, the control unit 10 sets the setting data for the projectionmode designated by the received mail in the units. Specifically, thecontrol unit 10 sets the driving mode data in the light sourcecontroller 2 and sets the image signal data in the display controller 4.The control unit 10 sets the diffusion degree data in the lightdiffusion controller 8. It is obvious that the setting data for theprojection mode is described in the mail treated in this step.

In step S10, the control unit 10 adjusts the light diffusion degree ofthe light diffusing device 7 to the projection mode. Specifically, thecontrol unit 10 adjusts the diffusion degree to be lower than adiffusion degree in the illumination mode for performing lighting forillumination and to be substantially zero (a state in which the light istransmitted without being substantially diffused). Consequently, forexample, even when characters are included in a projected image,deformation of the characters is reduced and the characters are clearlydisplayed.

In step S11, the control unit 10 executes projection specified by thesetting data for the projection mode of the received mail. Specifically,the control unit 10 drives to light the RGB light sources 1R, 1G, and 1Bat a driving frequency of a “normal mode” explained below and displaysthe message and the image designated by the mail on the spatial-lightmodulating device 3. To facilitate understanding of the explanation, thetwo steps S10 and S11 are dividedly explained. However, actually, thetwo steps are substantially simultaneously performed as a pair.

In step S12, the control unit 10 determines whether a projection timedesignated by the setting data of the received mail ends. When theprojection time ends (Yes in S12), the control unit 10 proceeds to stepS13. When the projection time does not end (No in S12), the control unit10 returns to step S11.

In step S13, the control unit 10 sets the setting data for theillumination mode stored in step S8 in the units again. Specifically,the control unit 10 sets the driving mode data in the light sourcecontroller 2 and sets the image signal data in the display controller 4.The control unit 10 sets the diffusion degree data in the lightdiffusion controller 8. When the setting of the setting data for theillumination mode ends, the control unit 10 proceeds to step S4 andchecks whether a new received mail is present. Even when the projectiontime ends in step S12, the control unit 10 continues the lighting in theprojection mode in step S11 until the next lighting (projection) begins.Consequently, it is possible to perform the projection (lighting)without a break. In this embodiment, as a preferred example, after theprojection time ends, the projection mode is returned to theillumination mode (the setting data) immediately before the projectionmode. However, the projection mode may be returned to the illuminationmode for initial illumination.

Contents of a Received Mail

FIGS. 5A and 5B are examples of operation instruction mails of theprojector 100. The examples of the operation instruction mails of theprojector 100 are explained.

A mail 50 shown in FIG. 5A is configured by a header 51 and content 52.The setting data explained above is described in the content 52. Thedata is not limited to be described in the content 52. The data may bedescribed in the header 51 or may be described in both the content 52and the header 51.

In a second row of the content 52, a C mode is set. Specifically, “0”described in a setting region of the C mode is an identifier. Thisindicates that processing is advanced in a normal flow. The settingregion means a region between <C_MODE> and <IC_MODE>. Concerning thefollowing modes and data, likewise, a region between <****> and </****>is a setting region. The C mode is explained in the second embodiment.

In a third row, the illumination mode or the projection mode is set.Specifically, “0” described in a setting region for a mode is anidentifier. This indicates the “illumination mode”. An identifier “1”indicates the “projection mode”.

In a fourth row, illumination color data specifying an illuminationcolor synthesized by the light sources 1R, 1G, and 1B is described.Specifically, “R,33;G,FF;B,FF” described in a setting region for data isthe illumination color data. In this case, a “bright light blue” issynthesized. In the case of this mail, setting of the “normal mode” andthe “high-speed mode” in the sequential driving is linked with thesetting of the illumination mode or the projection mode in the thirdrow. Specifically, designation of the illumination mode is set inassociation with the “high-speed mode” and designation of the projectionmode is set in association with the “normal mode”.

In a fifth row, diffusion degree data is described. Specifically, “50”described in a setting region for data is the diffusion degree data. Inthis case, the diffusion degree data is set to a diffusion degree “50%”.

In a sixth row, a diffusion time is described. In this mail, the sixthrow is a blank. In this case, the diffusion time is set to besynchronized with a display time in the next row.

In a seventh row, a display time is described. Specifically, “120”described in a setting region for data is time data. In this case, “120minutes” is the display time. When a power switch is turned off, even ifthe display time is less than a set time, display is forcibly finished.

In eighth and subsequent rows, display content is designated. Thedisplay content includes an image such as a photograph, a moving image,a message by text, and a link to a moving image (content) and the like.First, in the eighth and ninth rows, image data (display content)desired to be projected such as a photograph (an image) or a movingimage is attached. In this mail, nothing is attached. In this case, theimage data is a plain white (255 tone) image.

In the tenth and eleventh rows, a message (a text) is described asdisplay content. In this mail, nothing is attached. In this case, theimage data is a plain white image. Lighting by such setting data isplain bright light blue illumination.

Subsequently, illumination setting data of a mail 53 shown in FIG. 5B isexplained. Only differences from the explanation in FIG. 5A areexplained. The mail 53 is configured by a header 54 and content 55. Theillumination setting data is described in the content 55.

First, a difference from the mail 50 is that an identifier of a mode ina third row in the content 55 is “1” and the “projection mode” is set.Second, illumination color data in a fourth row is “R,FF;G,FF;B,FF”. Inthis case, “white light” is synthesized. Diffusion degree data in afifth row is “0”. In this case, a diffusion degree is set to “0%”. Asharp image is displayed.

In seventh and subsequent rows, display content is designated. Nothingis attached in the seventh and eighth rows. In the ninth to eleventhrows, a message (display content) “Welcome home. I'm out on urgentbusiness and will be back around 20:00.” is described. According to thisinstruction, the display controller 4 generates an image signal obtainedby superimposing the message on a plain image signal. The spatial-lightmodulating device 3 displays an image in which only a character portionis black (0 tone). In projection by such setting data for the projectionmode, as shown in FIG. 1, the message with black characters is clearlydisplayed in white illumination. In this example, since a charactercolor is not designated, standard black is applied. However, a commandfor designating the character color can also be added.

It is desirable to make it possible to easily create these mails byinputting the mails in a dedicated mail form using a GUI in a PC or asmart phone installed with a dedicated application program.

Driving Modes for the Light Sources

FIG. 6A is a driving timing chart in the normal mode. FIG. 6B is adriving timing chart in the high-speed mode. As explained above, thesequential driving for the RGB light sources is controlled to be thenormal mode in the projection mode and controlled to be the high-speedmode in the illumination mode. Details of the driving modes for thelight sources are explained.

Normal Mode

As shown in FIG. 6A, in the RGB sequential driving or the colorsequential driving, one frame of a frame color is represented bytemporally continuous three field images. When double speed driving isnot performed, if a frame frequency F_(frame) of a source image is 60Hz, an RGB repetition frequency F_(field) of a field image is 60 Hz. Forexample, in the case of triple speed driving, if the frame frequencyF_(frame) of the source image is 60 Hz, the RGB repetition frequencyF_(field) of the field image is 180 Hz. When the RGB light sources 1R,1G, and 1B are driven in the normal mode, R, G, and B LEDs aresequentially repeatedly driven to correspond to RGB field images. Atthis point, a repetition frequency n_(normal) of the RGB light sources1R, 1G, and 1G is 60 Hz (in the case of the triple speed driving, 180Hz). That is, in the normal mode, the RGB repetition frequency F_(field)of the field image and the repetition frequency n_(normal) of thesequentially driven RGB light sources 1R, 1G, and 1B are the same. Thenumber of element colors and the number of element light sources may belarger than three.

High-Speed Mode

As shown in FIG. 6B, a repetition frequency FL_(high) of the RGB lightsources 1R, 1G, and 1B in the case of the high-speed mode is higher thanthe RGB repetition frequency F_(field) of the field image written in thespatial-light modulating device 3 in the case of the normal mode.

Naturally, when the normal mode and the high-speed mode are defined, thenormal mode and the high-speed mode may be simply represented by thelevels of the repetition frequencies FL_(normal) and FL_(high) in themodes of the RGB light sources 1R, 1G, and 1B. The repetition frequencyFL_(high) in the high-speed mode is higher than the repetition frequencyFL_(normal) in the normal mode. In this embodiment, the repetitionfrequency FL_(high) in the high-speed mode is three times as high as therepetition frequency FL_(normal) in the normal mode.

In this embodiment, when the projector 100 is in the illumination mode,since the RGB light sources 1R, 1G, and 1B are driven in the high-speedmode, color breakup is less easily sensed than in the case of theprojection mode. In the case of the illumination mode, since timeperiods in which the R, G, and B LEDs can light (lighting possibleperiods) do not overlap, it is unnecessary to redundantly provide thesame circuits in a light-source driving circuit 25 (FIG. 7). Therefore,it is possible to simplify a circuit configuration. As in the case ofthe projection mode, since the RGB sequential driving is performed, itis possible to simplify driving control. That is, it is possible toprevent a cost increase in providing the projector 100 that functions aslighting equipment as well.

In FIG. 6B, an image (image data) for illumination projection is writtenin the spatial-light modulating device 3 in conjunction with the drivingof the RGB light sources 1R, 1G, and 1B in the high-speed mode. Thisimage is an image represented by, for example, a uniform luminancedistribution. The written image does not have to be particularlyrefreshed in the spatial-light modulating device 3 as shown in FIG. 6Bbut may be refreshed. When the written image is refreshed, the luminancedistribution of the written image may involve a change with time. It isdesirable to adjust timing for the refresh to any one of changes of thelighting possible periods of the respective RGB light sources 1R, 1G,and 1B because a visual beat less easily occurs. However, the frequencyof the refresh is desirably lower. This is because power consumption issmaller. Therefore, for example, it is conceivable that the writtenimage is refreshed at a frequency lower than the repetition frequency ofthe RGB light sources 1R, 1G, and 1B.

However, when the spatial-light modulating device 3 includes a liquidcrystal light valve of normally white (parallel Nicols), respectivepixel regions of the spatial-light modulating device 3 transmit lighteven if an image (image data) is not written. Therefore, in this case,when the RGB light sources 1R, 1G, and 1B are driven in the high-speedmode, the display controller 4 does not have to write an image in thespatial-light modulating device 3.

A color of light projected in the case of the high-speed mode can bechanged by changing a light emission intensity ratio among the RGB lightsources 1R, 1G, and 1B. The color of the light can also be changed bychanging pulse width (lighting period width) in the lighting possibleperiods of the respective RGB light sources 1R, 1G, and 1B.

Specific Hardware Configuration

FIG. 7 is a block diagram showing a form of a specific hardwareconfiguration.

The projector 100 is explained from the viewpoint of a more specifichardware configuration with reference to FIG. 7. The components alreadyexplained above are denoted by the same reference numerals and signs inthe figure and explanation of the components is sometimes omitted.

The projector 100 includes a bus 20, an image processing circuit 21configured to apply resolution conversion, color correction, andtrapezoidal correction to a source image, a light-valve driving circuit22 configured to give a driving signal to the spatial-light modulatingdevice 3 on the basis of the image processed by the image processingcircuit 21, the control unit 10, the power supply circuit 17electrically connected to the connecting unit 9, a light-source drivingcircuit 25 configured to give driving signals to the RGB light sources1R, 1G, and 1B, a light-diffusion driving circuit 26 configured to givea driving signal to the light diffusing device 7, and the IR receivingunit 11 configured to receive an infrared command from a remotecontroller. These components can communicate via the bus 20 under thecontrol by the control unit 10.

The light source controller 2 explained above is realized by the controlunit 10 and the light-source driving circuit 25. The display controller4 is realized by the control unit 10, the image processing circuit 21,and the light-valve driving circuit 22. The light diffusion controller 8is realized by the control unit 10 and the light-diffusion drivingcircuit 26. The function of the communication unit is realized by thecontrol unit 10 and the communication unit 12 configured by the wirelessLAN adapter. The configurations of these units are not limited to thehardware configuration in this embodiment and could include otherequivalent configurations that exhibit the same functions. The units canalso be respectively realized by dedicated hardware components.

“Illumination Mode” and “Projection Mode”

According to a broadest definition, the “illumination mode” refers to astate in which the projector 100 functions as lighting equipment andexhibits a function of providing “light” indoors or outdoors. Forexample, the “illumination mode” is a state in which the projector 100is projecting an image for illumination projection on a projectionsurface. The “illumination mode” is also defined as a state in which thelight diffusing device 7 is in the diffusing state. Alternatively, the“illumination mode” may be defined as a state in which the RGB lightsources 1R, 1G, and 1B are driven in the high-speed mode.

The “illumination mode” only has to be a mode in which at least one ofthe three conditions explained above is satisfied. Therefore, in somecase, even if the projector 100 is projecting a picture, a photograph, amoving image, or a computer screen, if the light diffusing device 7 isin the diffusing state or the RGB light sources 1R, 1G, and 1B aredriven in the high-speed mode, the projector 100 is referred to as beingin the “illumination mode”.

According to a broadest definition, the “projection mode” refers to astate in which the projector 100 is projecting some image. The“projection mode” is also defined as a state in which the lightdiffusing device 7 is in the non-diffusing state. Alternatively, the“projection mode” may be defined as a state in which the RGB lightsources 1R, 1G, and 1B are driven in the normal mode. An intermediatediffusion state of the light diffusing device 7 may be included in theprojection mode.

As explained above, with the projector 100 and the control method forthe projector 100 according to this embodiment, effects explained belowcan be obtained.

With the projector 100, for example, by mounting the connecting unit 9to a socket for illumination set in an entrance hall of an ordinaryhome, it is possible to easily attach a projector that can function aslighting equipment as well.

The projector 100 includes the communication unit configured to receivea mail (predetermined information). The projector 100 can update animage signal and adjust a diffusion degree of modulated light by thelight diffusing device 7 on the basis of contents of the mail receivedby the communication unit. Specifically, the projector 100 sets thediffusion degree to be lower than the diffusion degree in theillumination mode for performing lighting for illumination and to besubstantially zero.

Therefore, for example, when a user desires to inform family members whowill return home that the user suddenly has to go out, if the usertransmits in advance, to the projector, a mail including a message for afamily member who returns home, the family member who returns home turnson an illumination switch at the entrance, whereby the projector canstart up, perform the illuminating function, and clearly project anddisplay the message.

Therefore, it is possible to effectively utilize the illuminatingfunction for illuminating the entrance hall and the projecting functionfor displaying the message. In other words, it is possible to providethe projector 100 that can effectively utilize the illuminating functionand the projecting function and has high versatility.

Further, when the illumination mode is switched to the projection mode,since the brightness and the color tone of illumination change, it ispossible to cause the user to physically (visually) recognize thepresence of the message. Therefore, a degree of attention to the messageincreases and the message can be surely conveyed. Even in the projectionmode, since illuminace sufficient for visually recognizing an objectaround the user at night is secured, when the message is projected, theprojector 100 can perform a sufficient function of the lightingequipment.

It is possible to easily create setting data of a mail (predeterminedinformation) for operation instruction by inputting the setting data ina dedicated mail form using a GUI in a PC or a smart phone installedwith a dedicated application program. Therefore, it is possible toconveniently use the projector 100.

The projector 100 can also be easily operated by using a not-shownremote controller. As operation buttons of the remote controller, aswitching button for the illumination mode and the projection mode, anoperation button for each of a plurality of illumination patterns setfor each of usage scenes such as an illumination pattern for a party andan illumination pattern for relaxation, and the like are provided.Therefore, it is possible to provide the projector 100 that is easy touse and has high versatility.

Second Embodiment

FIG. 8 is a flowchart for explaining a flow of a control methodaccording to a second embodiment. The second embodiment is differentfrom the first embodiment in a part of the control method for theprojector 100. The configuration of the projector 100 is the same as theconfiguration in the first embodiment. In the control method accordingto this embodiment, a part of the control method according to the firstembodiment (FIG. 4) is changed. Therefore, redundant explanationconcerning common processing operations and the like is omitted. As inthe first embodiment, an operation flow shown in FIG. 8 is executed bythe control unit 10 controlling the units of the projector 100 includingthe communication unit 12 on the basis of the driving program stored inthe storing unit 19.

The control method according to this embodiment is effective for timelyinforming a user that a message (content) is received when it takes timeto read data, for example, when it is desired to display a message of amoving image in the projection mode. The control method makes itpossible to project “receiving a mail (data)” by adding determinationprocessing for presence or absence of application of the “C mode” to thebasic operation flow shown in FIG. 4 making use of the identifier of the“C mode” explained with reference to FIGS. 5A and 5B. The “C mode” isenabled when “1” is designated. Processing for timely projecting anindication that a received mail is present is performed in theprojection mode. When normal processing speed is acceptable, forexample, when a text message is mainly displayed, “0” is designated.

First, the control method according to this embodiment includes steps S1to S7 of the flowchart of FIG. 4 as a base (in common). However, thecontrol method is different in a routine from a branch (j) on the Noside in step S6 to a branch (k) for returning to step S4. In otherwords, in the control method according to this embodiment, theprocessing in steps S8 to S13 in FIG. 4 is replaced with processing insteps S21 to S34 in FIG. 8. Therefore, explanation of the common partsis omitted and the processing in steps S21 to S34 in FIG. 8 isexplained.

In step S21, the control unit 10 stores setting data for illuminationbeing executed (same as step S8 in FIG. 4).

In step S22, the control unit 10 determines whether “1” is designated toenable the C mode in the setting data of the received mail. When the Cmode is enabled (Yes in S22), the control unit 10 proceeds to step S23.When the C mode is not enabled (No in S22), the control unit 10 proceedsto step S30.

In step S23, the control unit 10 sets, in the units, setting dataincluding image signal data for displaying “receiving a mail (data)”.The setting data set when the C mode is enabled is stored in advance inthe storing unit 19 as standard data.

In step S24, the control unit 10 adjusts the light diffusion degree ofthe light diffusing device 7 to the projection mode. Specifically, thecontrol unit 10 adjusts the diffusion degree to be substantially zero.

In step S25, the control unit 10 executes projection specified in thesetting data set when the C mode is enabled. Specifically, “Receiving amessage. Please wait for a while.” is displayed with black characters inwhite light illumination. Display content is not limited to thissentence and only has to be a sentence or an image that can cause theuser to recognize that the projector 100 is “receiving a message”. Forexample, an image of a sand glass may be used.

In step S26, the control unit 10 reads image data (content) attached tothe received mail and sets projection setting data. The control unit 10accesses image data at a link destination (URL) designated by thereceived mail and performs streaming setting.

In step S27, the control unit 10 determines whether projection setting(preparation) ends. When the projection setting ends (Yes in S27), thecontrol unit 10 proceeds to step S28. When the projection setting doesnot end (No in S27), the control unit 10 returns to step S25 andcontinues the projection of “receiving a message”.

In step S28, the control unit 10 performs projection of the image dataattached to the received mail. Alternatively, the control unit 10performs streaming projection of the image data at the designated linkdestination (URL).

In step S29, the control unit 10 determines whether a projection timedesignated by the setting data of the received mail ends. When theprojection time ends (Yes in S29), the control unit 10 proceeds to stepS34. When the projection time does not end (No in S29), the control unit10 returns to step S28 and continues the projection.

In step S30, the control unit 10 sets the setting data designated by thereceived mail in the units (same as step S9 in FIG. 4).

In step S31, the control unit 10 adjusts the light diffusion degree ofthe light diffusing device 7 to the projection mode (same as step S10 inFIG. 4).

In step S32, the control unit 10 executes projection specified by thesetting data of the received mail (same as step S11 in FIG. 4).

In step S33, the control unit 10 determines whether the projection timedesignated by the setting data of the received mail ends. When theprojection time ends (Yes in S33), the control unit 10 proceeds to stepS34. When the projection time does not end (No in S33), the control unit10 returns to step S32 (same as step S12 in FIG. 4).

In step S34, the control unit 10 sets the setting data for illuminationstored in step S21 in the units again (same as step S13 in FIG. 4).After setting the setting data again, the control unit 10 returns tostep S4 (a branch k) in FIG. 4.

Contents of a Received Mail

FIG. 9 is an example of an operation instruction mail of the projector100 and corresponds to FIGS. 5A and 5B. A mail 56, which is an exampleof an operation instruction mail that enables the C mode, is explained.The mail 56 is configured by a header 57 and content 58. A basicconfiguration of a mail, an identifier, a type of data, and the like arethe same as those in the explanation in FIGS. 5A and 5B. Therefore, onlydifferences are explained.

First, in a second row of the content 58, the C mode is enabled bydesignating “1”. Consequently, processing for immediately projecting aprovisional message for informing that a received mail is present isperformed. In a third row, the projection mode “1” is designated.

Illumination color data in a fourth row is a blank (a space). Thisdesignates that the provisional message is projected on the basis of thestandard data stored in the storing unit 19 and that image data of thereceived mail is projected according to setting of the image data.

In diffusion degree data in a fifth row, “0” is designated and adiffusion degree is set to substantially zero. A display time in a sixthrow is a blank (a space). When the image data is a moving image, thedisplay time indicates time until reproduction of the moving image endsonce.

In seventh to ninth rows, content (a play list) desired to be projectedas a message is designated. Specifically, “http://www.*****.****.******”described in the eighth row is a URL for link to the image data(content). Consequently, a moving image or the like at a linkdestination (URL) is accessed and projection by streaming is executed.

Referring back to FIG. 8, in the flow of FIG. 8, it is explained thatthe indication that a message is being read is projected when theidentifier of the C mode is enabled. However, the identifier of the Cmode does not have to be used. For example, when a message is includedin a mail or in the case of the projection mode, the message readingindication may be displayed for all relevant mails. In this case, stepS22 and steps S30 to 33 are unnecessary. When the message is included orin the case of the projection mode, the message reading indication isinserted in all messages. In the case of a light message including onlya text, an indication that the message is being read in a short time isinserted in the message and the illumination mode is immediatelyswitched to projection of the message. Although this is unpleasant forsight, a sense of discomfort is reduced by, for example, setting themessage reading indication to be displayed at least for two seconds.

As explained above, with the control method for the projector 100according to this embodiment, in addition to the effects in the firstembodiment, effects explained below can be obtained.

With this control method, when a message (content) is included in areceived mail, before the message is projected, “Receiving a message.Please wait for a while.” is projected. Therefore, for example, whenmoving image is read from a link destination, even if it takes time toread the message, first, it is possible to surely inform that themessage is present.

If the identifier of the C mode is used, the user can select whether themessage receiving indication is displayed. Therefore, it is possible toeffectively utilize the projector 100 according to message contents.Therefore, it is possible to provide the projector 100 that is easy touse and can surely convey a message.

The present invention is not limited to the embodiments explained above.Various changes, improvements, and the like can be made to theembodiments. Modifications are explained below.

Modification 1

FIGS. 10A and 10B are diagrams showing forms of images in theillumination mode.

In the embodiments, as an example of the image signal in theillumination mode, the image signal specifying the plain image isexplained. However, an image is not limited to this configuration.Various images (hereinafter, “illumination images”) can be used.

For example, like an illumination image 60 shown in FIG. 10A, the imagemay be an image in which a plurality of circles having different tonesare concentrically arranged in the center of an external shape(substantially coinciding with the display surface of the spatial-lightmodulating device 3) of an image formed in a laterally long rectangularshape. Specifically, a circle 61 in the center has the highest tone(white: 255 tone), the tone gradually decreases toward the outer side,and the tone is the lowest (black: 0 tone) in the peripheral edge of therectangular shape (hereinafter referred to as “concentric image”). Inother words, the circle 61 in the center is an image having a gradationof tones.

Like an illumination image 62 shown in FIG. 10B, the image may be animage in which a plurality of concentric images are arranged.Specifically, a concentric image smaller than the concentric circleshown in FIG. 10A is arranged in the center and, on the outer side ofthe concentric circle, four smaller concentric circles 64 a to 64 d areevenly arranged in directions of 2 o'clock, 4 o'clock, 8 o'clock, and 10o'clock clockwise. The illumination image is not limited to a stillimage and may be a moving image. For example, the illumination image maybe a moving image in which the size of a concentric image in the centeris periodically changed or a moving image in which four concentricimages arranged around the concentric image in the center slowly revolvearound the concentric image in the center like satellites.

By using these illumination images in the illumination mode, it ispossible to perform illumination of a gradation gradually darkening fromthe circle 61 in the center even if the light diffusing device 7 is notused. In other words, it is possible to adjust a diffusion degree ofillumination according to an image signal even if the light diffusingdevice 7 is not used. Further, if these illumination images and thelight diffusing device 7 are combined, it is possible to realize moreexpressive illumination.

Modification 2

FIGS. 11A and 11B are diagrams showing different forms of a lightdiffusing device. The light diffusing device 7 shown in FIG. 2 may be,besides the PDLC device, a device that makes use of a diffuser or adevice that makes use of a lens for adjusting a focus or may be acombination of these three devices. A light diffusing device 71 in amodification 2 performs adjustment of a diffusion degree using adiffuser 72 as shown in FIG. 11A.

Specifically, when the diffuser 72 is used, the light diffusing device71 includes the diffuser 72 configured to diffuse and transmit light anda mechanical mechanism 73 configured to insert the diffuser 72 into anoptical path of the projector 100 and remove the diffuser 72 from theoptical path by sliding the diffuser 72. A position where the diffuser72 is inserted may be any position on the optical path and may be aposition on the optical path between the spatial-light modulating device3 and the RGB light sources 1R, 1G, and 1B. The same holds true in thecase of the reverse mode PDLC device and the case of the PDLC device.That is, the light diffusing device 71 may diffuse any of light madeincident on the spatial-light modulating device 3 and light emitted fromthe spatial-light modulating device 3. However, a position further onthe outer side than a projection lens on the outermost side is desirablebecause lights from the RGB light sources 1R, 1G, and 1B can beefficiently used in the case of the illumination mode.

The diffuser 72 may have the shape of a wheel. In this case, thediffuser 72 may include a portion for diffusing light (a portion havinga high diffusion degree), a portion for transmitting the light withoutsubstantially diffusing the light (a portion having a low diffusiondegree), and a portion having an intermediate diffusion degree. Themechanism 73 rotates the wheel according to the control by the lightdiffusion controller 8, whereby any one of the three portions is locatedon the optical path of the projector 100.

When a lens for adjusting a focus (a focus lens) is used, the lens onlyhas to be controlled to be focused on a projection surface in theprojection mode and controlled to be defocused in the illumination mode.

Modification 3

A modification 3 is explained with reference to FIG. 2.

In the explanation in the embodiments explained above, the light sourceof the projector 100 is configured to sequentially drive the LED lightsources of the respective colors RGB. However, the light source is notlimited to this configuration. For example, a light source that emitswhite light may be used.

Specifically, as the white light source, a white LED or EL element issuitable. In the case of this configuration, the solid-state lightsource is arranged instead of the dichroic prism of the irradiationoptical system 5. As the spatial-light modulating device 3, asingle-panel transmissive color liquid crystal light valve including RGBcolor filters is used. As the white light source, discharge-type lampssuch as a halogen lamp, a metal halide lamp, and a high-pressure mercurylamp may be used. With these configurations, the functions of theprojector 100 can be obtained and, moreover, the configuration of theprojector 100 is simplified because only one light source is used.Further, it is possible to simplify a lighting driving method (circuit)as well.

Modification 4

According to the embodiments, the spatial-light modulating device 3 isthe single-panel transmissive liquid crystal light valve. However, thespatial-light modulating device 3 may include a reflective liquidcrystal light valve or may include a digital mirror device (DMD). Whenthe spatial-light modulating device 3 includes the reflective liquidcrystal light valve, the digital mirror device, or other light valves,it is obvious for those skilled in the art how the irradiation opticalsystem 5 and the projection optical system 6 should be modified.

Modification 5

In the explanation in the embodiments, when electric power is suppliedto the projector 100 (the power SW is turned on), the projector 100enters the “illumination mode”. However, the projector 100 is notlimited to this configuration. The projector 100 may start from the“projection mode”. In the “projection mode”, for example, even when a“totally black” image is projected, since illuminance sufficient for theuser to check a situation around the user at night is secured, theprojector 100 can perform the function of illumination. If an initialstate is the “projection mode”, it is possible to more timely performmessage display.

Modification 6

With the projector 100, the light diffusing device 7 can periodicallyrepeat transition between the diffusing state and the non-diffusingstate. Such periodical repetition can be attractive production ofillumination. When the light diffusing device 7 is diffusing light, theprojector 100 projects an image for illumination projection. When thelight diffusing device 7 is not substantially diffusing light, theprojector 100 projects an image for image projection. Alternatively,even if the light diffusing device 7 is diffusing light or not, theprojector 100 may project an image based on image data.

Modification 7

In the explanation in the embodiments, the projector 100 is set on theceiling of the entrance hall. However, the projector 100 is not limitedto this configuration. The projector 100 can be set in various places inthe home. For example, the projector 100 may be set in a kitchen, adining room, a living room, a study, or a bedroom. It is convenient toset the projector 100 on the ceiling of the kitchen because a recipe ofcooking can also be projected in the projection mode. When the projector100 is set in the living room, if the user desires to calm down theuser's emotion, the user can obtain a relaxation effect by performingslowly-moving illumination using the illumination images shown in FIGS.10A and 10B. The use of the projector 100 is not limited to uses in thehome. The projector 100 may be used outdoors and can be used in variousplaces, for example, in a train, in a vehicle such as a bus, and in acabin of an airplane.

What is claimed is:
 1. A projector comprising: a connecting unit formounting the projector to a socket for lighting equipment; a lightsource configured to emit light with electric power supplied to theconnecting unit; a light modulating unit configured to convert the lightemitted by the light source into modulated light specified by an imagesignal; a diffusion adjusting unit configured to adjust a diffusiondegree of the light made incident on the light modulating unit or thelight emitted from the light modulating unit; a communication unitconfigured to receive predetermined information via a communicationnetwork; and a control unit configured to update the image signal andcontrol the adjustment of the diffusion degree by the diffusionadjusting unit on the basis of contents of the predetermined informationreceived by the communication unit.
 2. The projector according to claim1, wherein the control unit switches, on the basis of the contents ofthe predetermined information, an illumination mode for causing thediffusion adjusting unit to diffuse the light and a projection mode inwhich the diffusion degree is lower than the diffusion degree in theillumination mode.
 3. The projector according to claim 2, wherein, whencontent for display is included in the received predeterminedinformation, the control unit superimposes the content on the imagesignal and sets the diffusion degree to the projection mode.
 4. Theprojector according to claim 3, wherein, when content is included in thereceived predetermined information, the control unit superimposes, onthe image signal, an image indicating that the content is being readbefore performing superimposition of the content.
 5. The projectoraccording to claim 3, wherein, when a link to content is included in thepredetermined information, the content is read from the link destinationvia the communication network.
 6. The projector according to claim 2,further comprising a storing unit configured to store setting dataincluding an image signal used in the illumination mode, wherein whenelectric power is supplied to the connecting unit, the control unitcauses, on the basis of the setting data, the light modulating unit tomodulate the light emitted by the light source.
 7. The projectoraccording to claim 6, wherein the setting data includes the image signalincluding an image having a gradation of tones.
 8. The projectoraccording to claim 6, wherein the setting data includes, in addition tothe image signal, at least one of diffusion degree data representing thediffusion degree of the diffusion adjusting unit, an identifier fordesignating the illumination mode or the projection mode, illuminationcolor data designating an illumination color in the illumination mode,and time data designating duration of the illumination mode or theprojection mode.
 9. The projector according to claim 1, wherein thediffusion adjusting unit includes a PDLC device or a reverse mode PDLCdevice.
 10. The projector according to claim 1, wherein the diffusionadjusting unit includes a focus adjusting lens or a diffuser configuredto transmit and diffuse the light.
 11. A control method for a projectorincluding: a connecting unit for mounting the projector to a socket forlighting equipment; a light source configured to emit light withelectric power supplied to the connecting unit; a light modulating unitconfigured to convert the light emitted by the light source intomodulated light specified by an image signal; a diffusion adjusting unitconfigured to adjust a diffusion degree of the light made incident onthe light modulating unit or the light emitted from the light modulatingunit; and a communication unit configured to receive predeterminedinformation via a communication network, the control method comprising:allowing the communication unit to receive the predeterminedinformation; and updating the image signal and controlling theadjustment of the diffusion degree by the diffusion adjusting unit onthe basis of contents of the predetermined information received by thecommunication unit.